EPRO MMS3120-022-100 Eddy Current Sensor

Configured for shaft displacement and vibration measurement in turbomachinery protection systems, the EPRO MMS3120-022-100 (PR6423 Eddy Current Sensor) provides direct physical/electrical execution. The contactless non-contact transducer converts mechanical distance variations between the probe tip and rotating target surfaces into proportional dynamic high-frequency impedance changes.

Hardware Specifications

Rotor Dynamics & Eddy-Current Probe Scaling

High-speed turbomachinery analysis requires linear eddy-current probe scaling aligned with specific target shaft metallurgy and excitation frequency. Accurate static position and dynamic vibration monitoring depend on gap voltage validation (-10 VDC targets) measured at the signal converter output to confirm probe installation at the midpoint of its linear range. Maintaining precise orthogonal probe placement on bearing housings supports effective cross-talk suppression between adjacent radial X and Y vibration channels.

Frequently Asked Questions

Q: What output parameter verifies proper static mechanical positioning during installation?

A: Static mechanical gap setup is verified by measuring the driver output voltage, adjusting the sensor insertion depth until reaching an approximate -10 VDC baseline bias voltage.

Q: How does target shaft metallurgy affect transducer output?

A: Variations in magnetic permeability and electrical conductivity alter eddy current penetration depth, requiring calibrated probe scaling matched to the target shaft material composition.

Field Installation Guidelines

• Probe Gap Setting: Thread sensor into mounting fixture by hand until reaching mechanical contact with shaft target, then reverse probe position while monitoring output bias voltage until -10 VDC baseline is achieved.
• Mechanical Fastening: Torque external jam nut against mounting surface according to standard thread specifications to maintain mechanical stability under machine vibration.
• Cable Protection: Route integral coaxial cable through protective flexible conduit, keeping minimum cable bend radius above 30 mm to prevent shield or conductor degradation.
• Shield Grounding: Ground instrument cable shielding at the monitor panel earth bus bar only, maintaining isolation at the machine casing to prevent ground loops.